Congestion/overload control method and apparatus

ABSTRACT

Embodiments of the present invention provide a congestion/overload control method and apparatus. The method includes: learning, by a gateway device, information about network access time of a User Equipment (UE) or UE group; and rejecting or discarding, by the gateway device, session management request messages of the UE or UEs in the UE group beyond the network access time of the UE or UE group; or discarding, by the gateway device, data of the UE or the UEs in the UE group beyond the network access time of the UE or UE group. Embodiments of the present invention can perform congestion/overload control differentially on the UE or UEs in the group, implement congestion/overload control on the gateway device, avoid congestion/overload caused by a large number of UEs on the gateway device, and improve the efficiency of congestion/overload control.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation U.S. patent application Ser. No.13/657,287, filed on Oct. 22, 2012, which is a continuation ofInternational Patent Application No. PCT/CN2010/072051, filed on Apr.22, 2010. The afore-mentioned patent applications are herebyincorporated by reference in their entireties.

FIELD OF THE INVENTION

The present invention relates to the field of communicationtechnologies, and in particular, to a congestion/overload control methodand apparatus.

BACKGROUND OF THE INVENTION

In Machine Type Communications (Machine Type Communications, MTC)applications with a large number of User Equipments (User Equipments,UEs), multiple UEs (UEs of MTC applications) may constitute a whole,which is hereinafter referred to as a group or a UE group, so thatnetwork operators or MTC users may manage and control the group as awhole. When a large number of such UEs access the network, a mobilitymanagement element may be congested/overloaded, and thereforecongestion/overload control is performed. The mobility managementelement may select one or several gateway devices for a group of UEs,that is, different UEs in the same group may be connected to one orseveral gateway devices through different mobility management elements.Therefore, the mobility management element may converge connectivityrequests of the UEs in the group in the network to one or severalgateway devices. Even if the mobility management element is notcongested/overloaded, the gateway device may be congested/overloadedunder the impact of a large amount of signaling.

In the process of implementing the present invention, the inventor findsat least the following problems in the prior art:

The mobility management element can perform congestion/overload controlto control the access of the UE according to only its own stateinformation, but cannot learn whether the gateway device is in thecongested/overloaded state. Therefore, the mobility management elementcannot perform congestion/overload control; as a result, theconnectivity requests initiated by the subsequent UEs impact the gatewaydevice, and the congestion/overload of the gateway device may get moreserious. Consequently, the gateway device cannot work normally.

Further, if the mobility management element is in thecongested/overloaded state, the mobility management element notifies anaccess network element to perform congestion/overload control, and theaccess network element does not differentiate UEs when performingcongestion/overload control. In Machine to Machine (Machine to Machine,M2M) applications, because a lot of MTC users exist, service features ofM2M applications of different MTC users are different. Therefore, theM2M applications of some specific MTC users cause networkcongestion/overload, for example, UEs of some MTC users initiate anaccess or detach procedure to the network frequently, resulting innetwork congestion or overload. Even if the network device can performcongestion/overload control on the gateway device, the network devicecannot differentiate and control the UEs that cause congestion/overloadof the gateway device, thereby reducing the efficiency ofcongestion/overload control.

SUMMARY OF THE INVENTION

Embodiments of the present invention provide a congestion/overloadcontrol method and apparatus, which can implement congestion/overloadcontrol on a gateway device, avoid congestion/overload caused by a largenumber of UEs on the gateway device, and improve the efficiency ofcongestion/overload control.

An embodiment of the present invention provides a congestion/overloadcontrol method, including:

learning, by a gateway device, information about network access time ofa UE or UE group; and

rejecting or discarding, by the gateway device, session managementrequest messages of the UE or UEs in the UE group beyond the networkaccess time of the UE or UE group; or

discarding, by the gateway device, data of the UE or the UEs in the UEgroup beyond the network access time of the UE or UE group.

An embodiment of the present invention provides anothercongestion/overload control method, including:

learning, by a gateway device, information about a congestion/overloadcontrol parameter or policy of a UE group; and

if the congestion/overload control parameter or policy of the UE groupis reached or exceeded,

rejecting or discarding, by the gateway device, session managementrequest messages of UEs in the UE group, or

discarding, by the gateway device, data of the UEs in the UE group, or

deleting, by the gateway device, bearers or PDP contexts of the UEs inthe UE group, or

discarding, by the gateway device, data that exceeds thecongestion/overload control parameter or policy of the UE group, or

charging, by the gateway device, for the data that exceeds thecongestion/overload control parameter or policy of the UE group.

An embodiment of the present invention provides still anothercongestion/overload control method, including:

receiving an indication message sent by a gateway device, where theindication message indicates that the gateway device iscongested/overloaded or that an application server isfailed/congested/overloaded/unreachable/misbehaving; and

selecting other gateway devices for UEs that access the gateway device;or

rejecting or discarding access request messages of UEs served by thegateway device or the application server; or

detaching UEs on the gateway device or the application server; or

deleting bearers of the UEs on the gateway device or the applicationserver.

An embodiment of the present invention provides a gateway device,including:

a learning module, adapted to learn information about network accesstime of a UE or UE group; and

a controlling module, adapted to: beyond the network access time of theUE or UE group, reject or discard session management request messages ofthe UE or UEs in the UE group, or discard data of the UE or the UEs inthe UE group.

An embodiment of the present invention provides another gateway device,including:

a learning module, adapted to learn information about acongestion/overload control parameter or policy of a UE group; and

a controlling module, adapted to: if the congestion/overload controlparameter or policy of the UE group is reached or exceeded, reject ordiscard session management request messages of UEs in the UE group, ordiscard data of the UEs in the UE group, or delete bearers or PDPcontexts of the UEs in the UE group, or discard data that exceeds thecongestion/overload control parameter or policy of the UE group, orcharge for the data that exceeds the congestion/overload controlparameter or policy of the UE group.

An embodiment of the present invention provides still another gatewaydevice, including a sending module adapted to send an indication messageto a mobility management element, where the indication message indicatesthat the gateway device is congested/overloaded or that an applicationserver is failed/congested/overloaded/unreachable/misbehaving, so thatthe mobility management element selects other gateway devices for UEsthat access the gateway device, or rejects or discards access requestmessages of UEs served by the gateway device or the application server,or detaches UEs on the gateway device or the application server, ordeletes bearers of the UEs on the gateway device or the applicationserver.

An embodiment of the present invention provides a mobility managementelement, including:

a receiving module, adapted to receive an indication message sent by agateway device, where the indication message indicates that the gatewaydevice is congested/overloaded or that an application server isfailed/congested/overloaded/unreachable/misbehaving; and

a controlling module, adapted to: select other gateway devices for UEsthat access the gateway device; or reject or discard access requestmessages of UEs served by the gateway device or the application server;or detach UEs on the gateway device or the application server; or deletebearers of the UEs on the gateway device or the application server.

As seen from the above technical solutions, by using thecongestion/overload control method in the embodiments of the presentinvention, when the gateway device is congested/overloaded, the gatewaydevice may perform congestion/overload control differentially on a UE orUEs in a UE group according to the learned information about the networkaccess time of the UE or UE group or according to the learnedinformation about the congestion/overload control parameter or policy ofthe UE group, so that congestion/overload control can be performed onthe gateway device, congestion/overload caused by a large number of UEson the gateway device is avoided, and the efficiency ofcongestion/overload control is improved.

BRIEF DESCRIPTION OF THE DRAWINGS

To describe the technical solutions in the embodiments of the presentinvention or in the prior art more clearly, the following outlines theaccompanying drawings required in the description of the embodiments orthe prior art. Apparently, the accompanying drawings illustrate onlysome exemplary embodiments of the present invention, and persons ofordinary skill in the art can derive other drawings from theaccompanying drawings without creative efforts.

FIG. 1 is a schematic flowchart of a congestion/overload control methodaccording to a first embodiment of the present invention;

FIG. 2 is a schematic flowchart of a congestion/overload control methodaccording to a second embodiment of the present invention;

FIG. 3 is a schematic flowchart of another congestion/overload controlmethod according to a third embodiment of the present invention;

FIG. 4 is a schematic flowchart of another congestion/overload controlmethod according to a fourth embodiment of the present invention;

FIG. 5 is a schematic flowchart of still another congestion/overloadcontrol method according to a fifth embodiment of the present invention;

FIG. 6 is a schematic flowchart of still another congestion/overloadcontrol method according to a sixth embodiment of the present invention;

FIG. 7 is a schematic structural diagram of a gateway device accordingto a seventh embodiment of the present invention;

FIG. 8 is a schematic structural diagram of another gateway deviceaccording to an eighth embodiment of the present invention;

FIG. 9 is a schematic structural diagram of still another gateway deviceaccording to a ninth embodiment of the present invention;

FIG. 10 is a schematic structural diagram of still another gatewaydevice according to a tenth embodiment of the present invention; and

FIG. 11 is a schematic structural diagram of a mobility managementelement according to an eleventh embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The technical solutions provided in the embodiments of the presentinvention are hereinafter described clearly and completely withreference to the accompanying drawings. Apparently, the embodiments areonly exemplary embodiments of the present invention and the presentinvention is not limited to such embodiments. Other embodiments thatpersons skilled in the art obtain based on the embodiments of thepresent invention also fall within the scope of the present invention.

FIG. 1 is a schematic flowchart of a congestion/overload control methodaccording to a first embodiment of the present invention. The UE in thisembodiment is a time controlled UE, and specifically, the UE can onlyinitiate a service within the defined (subscribed or configured) time.As shown in FIG. 1, the congestion/overload control method in thisembodiment may include the following steps:

Step 101: A gateway device learns information about network access timeof a UE or UE group (such as authorized/allowed/access grant timeperiods).

Step 102: The gateway device rejects or discards session managementrequest messages of the UE or UEs in the UE group beyond the networkaccess time of the UE or UE group; or

the gateway device discards data of the UE or the UEs in the UE groupbeyond the network access time of the UE or UE group.

By using the congestion/overload control method provided in thisembodiment, when the gateway device is congested/overloaded, the gatewaydevice may perform congestion/overload control differentially on the UEor UEs in the UE group according to the learned information about thenetwork access time of the UE or UE group, so that congestion/overloadcontrol can be performed on the gateway device, congestion/overloadcaused by a large number of UEs on the gateway device is avoided, andthe efficiency of congestion/overload control is improved.

In step 101 of this embodiment, the gateway device may learn theinformation about the network access time of the UE or UE group in thefollowing modes:

A. Learn the information about the network access time of the UE or UEgroup from a mobility management element.

Specifically, after learning the information about the network accesstime of the UE or UE group, the mobility management element may send thetime information to the gateway device through a session managementmessage, for example, Create PDP Context Request message, or CreateSession Request message. The mobility management element may learn thetime information in the following modes:

a. Learn the information about the network access time of the UE or UEgroup from a subscription profile repository.

After receiving an access request message sent by the UE, the mobilitymanagement element may learn subscription data of the UE or UE groupfrom the subscription profile repository such as a Home LocationRegister (Home Location Register, HLR) or a Home Subscriber Server (HomeSubscriber Server, HSS), where the subscription data includes theinformation about the network access time of the UE or information aboutthe network access time of the UE group. The specific mode may be: themobility management element sends an Update Location Request message tothe subscription profile repository; after receiving the Update LocationRequest message, the subscription profile repository returns theinformation about the network access time of the UE or UE group in thesubscription data to the mobility management element through an UpdateLocation Ack message.

The access request message may be an Attach Request message, a RoutingArea Update Request message, a Tracking Area Update Request message, aService Request message, a Packet Data Network (PDN) ConnectivityRequest message, or an Activate PDP Context Request message.

b. Learn the information about the network access time of the UE or UEgroup from UE contexts.

Specifically, if UE contexts are stored on the mobility managementelement, the mobility management element may also learn the informationabout the network access time of the UE or UE group from the UEcontexts.

c. Learn the information about the network access time of the UE or UEgroup from configuration information.

The mobility management element may configure the information about thenetwork access time of the UE or UE group according to an ID of the UEgroup (referred to as a group ID), and learn information about thenetwork access time of the UE or UE group from the configurationinformation. The group ID is used to identify a group, and the group maybe a UE group, a Machine to Machine (Machine to Machine, M2M) MTC user,an M2M application subscriber (an MTC subscriber or an MTC server), orother groups consisting of multiple devices, which is not limited inthis embodiment. The group ID above may be a UE group ID, or an IDshared by multiple UEs in a group, for example, an International MobileSubscriber Identification Number (International Mobile SubscriberIdentification Number, IMSI), a Mobile Station International IntegratedServices Digital Network Number (Mobile Station International IntegratedServices Digital Network Number, MSISDN), or an International MobileEquipment Identity (International Mobile Equipment Identity, IMEI), ormay also be an IMSI segment or an MSISDN segment, or may also be otherIDs that can indicate a group, for example, an Access Point Name (AccessPoint Name, APN). This embodiment does not limit the form of the groupID.

B. Learn the information about the network access time of the UE or UEgroup from configuration information.

The gateway device may configure the information about the networkaccess time of the UE or UE group according to an ID of the UE group(referred to as a group ID), and learn the information about the networkaccess time of the UE or UE group from the configuration information.Specifically, the gateway device may learn the UE ID or UE group IDthrough a session management message sent by the mobility managementelement, for example, Create PDP Context Request message, or CreateSession Request message, and learn the information about the networkaccess time of the UE or UE group from the configuration informationaccording to the UE ID or UE group ID.

C. Learn the information about the network access time of the UE or UEgroup from a database.

Specifically, the gateway device may learn the UE ID or UE group IDthrough a session management message sent by the mobility managementelement, for example, Create PDP Context Request message, or CreateSession Request message, and query a database such as an Authentication,Authorization and Accounting (Authentication, Authorization andAccounting, AAA) server for the information about the network accesstime of the UE or UE group according to the UE ID or UE group ID.

In step 102 of this embodiment, the gateway device in thecongested/overloaded state may perform congestion/overload control inthe following modes according to the learned information about thenetwork access time of the UE or UE group:

A. Beyond the network access time of the UE, reject or discard thesession management request message of the UE.

Specifically, when the gateway device is in the congested/overloadedstate, if beyond the network access time of the UE (for example, beyondthe time range identified by the information about the network accesstime of the UE), the gateway device receives a session managementrequest message sent by the mobility management element for the UE, forexample, Create PDP Context Request message, Create Session Requestmessage, or Modify Bearer Request message, the gateway device rejects ordiscards the session management request message. Optionally, the gatewaydevice may accept or reject or discard the session management requestmessage according to indication information indicating whether to allowaccepting the session management request of the UE beyond the networkaccess time of the UE. For example, if the indication informationindicates that the session management request of the UE is not allowedto be accepted beyond the network access time of the UE, the gatewaydevice rejects or discards the session management request message of theUE beyond the network access time of the UE.

The indication information indicating whether to allow accepting thesession management request of the UE beyond the network access time ofthe UE may be configured on the gateway device. For example, afterreceiving the session management request message sent by the mobilitymanagement element, the gateway device queries the configurationinformation according to the UE ID in the session management requestmessage, and learns the indication information indicating whether toallow accepting the session management request of the UE beyond thenetwork access time of the UE. Alternatively, the indication informationindicating whether to allow accepting the session management request ofthe UE beyond the network access time of the UE may be defined in thesubscription data. For example, the mobility management element learnsfrom the subscription data the indication information indicating whetherto allow accepting the session management request of the UE beyond thenetwork access time of the UE, and then sends the indication informationindicating whether to allow accepting the session management request ofthe UE beyond the network access time of the UE to the gateway devicethrough a session management request message.

Optionally, the gateway device may also carry time indicationinformation (called first time indication information) (back-off time)(for example, duration or time point) and/or a cause value in a sessionmanagement reject message returned to the mobility management element.After receiving the first time indication information and/or causevalue, the mobility management element may perform the followingprocessing:

1. The mobility management element sends the first time indicationinformation and/or cause value to the UE (for example, the mobilitymanagement element sends the first time indication information and/orcause value to the UE through an access request reject message). Or

2. The mobility management element generates time indication information(called second time indication information) and/or cause valueinformation according to the received first time indication informationand/or cause value, and sends the generated second time indicationinformation and/or cause value information to the UE. For example, afterlearning the first time indication information sent by the gatewaydevice, the mobility management element receives an access request sentby the UE, subtracts the time of receiving the access request sent bythe UE from the first time indication information, and uses the obtainedresult as the value of the second time indication information. Or

3. The mobility management element performs access control (for example,rejects or discards the access request message of the UE) according tothe first time indication information and/or cause value. Specifically,the first time indication information may be used to instruct themobility management element to reject or discard the access requestmessage of the UE within the time range indicated by the first timeindication information (for example, before the first time indicationinformation expires); or the first time indication information may beused to instruct the mobility management element to accept the accessrequest message of the UE beyond the time range indicated by the firsttime indication information (for example, after the first timeindication information expires); the cause value may be used to notifythe mobility management element that the gateway device is in thecongested/overloaded state. Or

4. The mobility management element performs access control according tothe first time indication information and/or cause value (described in3), and sends the first time indication information and/or cause valueto the UE (for example, the mobility management element sends the firsttime indication information and/or cause value to the UE through anaccess request reject message).

In addition, after receiving the session reject request message of thegateway device, the mobility management element may generate (provide)the second time indication information and/or cause value information,and send the second time indication information and/or cause valueinformation to the UE (for example, the mobility management elementsends the second time indication information and/or cause valueinformation to the UE through an access request reject message). Forexample, the mobility management element generates second timeindication information and/or cause value information according toconfiguration information (the value of the second time indicationinformation configured on the mobility management element).

The second time indication information sent by the mobility managementelement to the UE is used to instruct the UE not to initiate an accessrequest frequently or immediately. Specifically, the second timeindication information may be used to instruct the UE not to send anaccess request message within the time range indicated by the secondtime indication information (for example, before the second timeindication information expires); or the second time indicationinformation may also be used to instruct the UE to send an accessrequest message beyond the time range indicated by the second timeindication information (for example, after the second time indicationinformation expires); the cause value information may be further used toinstruct the UE not to send an access request message frequently orimmediately. According to the second time indication information and/orcause value information sent by the mobility management element to theUE, the UE will not initiate an access request frequently orimmediately, which reduces the frequent and repeated signaling impactcaused by a large number of UEs on the network, and avoids networkcongestion or overload caused by the impact of a large amount ofsignaling.

B. Beyond the network access time of the UE group, reject or discard thesession management request message of UEs in the UE group.

Specifically, when the gateway device is in the congested/overloadedstate, if beyond the network access time of the UEs in the UE group (forexample, beyond the time range identified by the information about thenetwork access time of the UE group), the gateway device receives thesession management request message sent by the mobility managementelement for the UEs in the UE group, for example, Create PDP ContextRequest message, Create Session Request message, or Modify BearerRequest message, the gateway device rejects or discards the sessionmanagement request message. Optionally, the gateway device may accept orreject or discard the session management request message according tothe indication information indicating whether to allow accepting thesession management request of the UEs in the UE group beyond the networkaccess time of the UE group. For example, if the indication informationindicates that the session management request of the UEs in the UE groupis not allowed to be accepted beyond the network access time of the UEgroup, the gateway device rejects or discards the session managementrequest message of the UEs in the UE group beyond the network accesstime of the UE group.

The indication information indicating whether to allow accepting thesession management request of the UEs in the UE group beyond the networkaccess time of the UE group may be configured on the gateway device. Forexample, after receiving the session management request message sent bythe mobility management element, the gateway device queries theconfiguration information according to the UE ID or UE group ID in thesession management request message, and learns the indicationinformation indicating whether to allow accepting the session managementrequest of the UEs in the UE group beyond the network access time of theUE group. Alternatively, the indication information indicating whetherto allow accepting the session management request of the UEs in the UEgroup beyond the network access time of the UE group may be defined inthe subscription data. For example, the mobility management elementlearns from the subscription data the indication information indicatingwhether to allow accepting the session management request of the UEs inthe UE group beyond the network access time of the UE group, and thensends the indication information indicating whether to allow acceptingthe session management request of the UEs in the UE group beyond thenetwork access time of the UE group to the gateway device through asession management request message.

Further, the gateway device may reject or discard, according to apercentage, the session management request message sent by the mobilitymanagement element for the UEs in the UE group. When the gateway deviceis in the congested/overloaded state, if the gateway device receives thesession management request message sent by the mobility managementelement for the UEs in the UE group beyond the network access time ofthe UEs in the UE group, the gateway device rejects or discards thesession management request message according to the percentage.

Optionally, the gateway device may also carry time indicationinformation (called first time indication information) (back-off time)(for example, duration or time point) and/or a cause value in a sessionmanagement reject message returned to the mobility management element.

After receiving the first time indication information and/or causevalue, the mobility management element may perform the followingprocessing:

1. The mobility management element sends the first time indicationinformation and/or cause value to the UE (for example, the mobilitymanagement element sends the first time indication information and/orcause value to the UE through an access request reject message). Or

2. The mobility management element generates time indication information(called second time indication information) and/or cause valueinformation according to the received first time indication informationand/or cause value, and sends the generated second time indicationinformation and/or cause value information to the UE. For example, afterlearning the first time indication information sent by the gatewaydevice, the mobility management element receives an access request sentby the UE, subtracts the time point of receiving the access request sentby the UE from the first time indication information, and uses theobtained result as the value of the second time indication information.Or

3. The mobility management element performs access control (for example,rejects or discards the access request message of the UE) according tothe first time indication information and/or cause value. Specifically,the first time indication information may be used to instruct themobility management element to reject or discard the access requestmessage of the UEs in the UE group within the time range indicated bythe first time indication information (for example, before the firsttime indication information expires); or the first time indicationinformation may be used to instruct the mobility management element toaccept the access request message of the UEs in the UE group beyond thetime range indicated by the first time indication information (forexample, after the first time indication information expires). Or

4. The mobility management element performs access control according tothe first time indication information and/or cause value (described in3), and sends the first time indication information and/or cause valueto the UE (for example, the mobility management element sends the firsttime indication information and/or cause value to the UE through anaccess request reject message).

In addition, after receiving the session reject request message of thegateway device, the mobility management element may generate (provide)the second time indication information and/or cause value information,and send the second time indication information and/or cause valueinformation to the UE (for example, the mobility management elementsends the second time indication information and/or cause valueinformation to the UE through an access request reject message). Forexample, the mobility management element generates second timeindication information and/or cause value information according toconfiguration information (the value of the second time indicationinformation configured on the mobility management element).

The second time indication information sent by the mobility managementelement to the UE is used to instruct the UE not to initiate an accessrequest frequently or immediately. Specifically, the second timeindication information may be used to instruct the UEs in the UE groupnot to send access request messages within the time range indicated bythe second time indication information (for example, before the secondtime indication information expires); or the second time indicationinformation may also be used to instruct the UEs in the UE group to sendaccess request messages beyond the time range indicated by the secondtime indication information (for example, after the second timeindication information expires); the cause value information may befurther used to instruct the UEs in the UE group not to send accessrequest messages frequently or immediately. According to the second timeindication information and/or cause value information sent by themobility management element to the UE, the UE will not initiate anaccess request frequently or immediately, which reduces the frequent andrepeated signaling impact caused by a large number of UEs on thenetwork, and avoids network congestion or overload caused by the impactof a large amount of signaling.

C. Discard data of the UE or the UEs in the UE group beyond the networkaccess time of the UE or UE group.

Specifically, when the gateway device is in the congested/overloadedstate, if beyond the network access time of the UE or UEs in the UEgroup (for example, beyond the time range identified by the informationabout the network access time of the UE or UE group), the gateway devicereceives data of the UE or UEs in the UE group, the gateway devicediscards the data. For example, beyond the network access time of the UEor UEs in the UE group, the gateway device may set the bearer gatestatus of the UE or UEs in the UE group to closed; when the gatewaydevice receives the data of the UE or UEs in the UE group, the gatewaydevice may discard the data. Optionally, the gateway device may acceptor discard the data of the UE or UEs in the UE group according toindication information indicating whether to allow accepting the data ofthe UE or UEs in the UE group beyond the network access time of the UEor UE group. For example, if the indication information indicates thatthe data of the UE or UEs in the UE group is not allowed to be acceptedbeyond the network access time of the UE or UE group, the gateway devicediscards the data of the UE or UEs in the UE group beyond the networkaccess time of the UE or UE group.

The indication information indicating whether to allow accepting thedata of the UE or UEs in the UE group beyond the network access time ofthe UE or UE group may be configured on the gateway device. For example,after receiving the session management request message sent by themobility management element, the gateway device queries theconfiguration information according to the UE ID or UE group ID in thesession management request message, and learns the indicationinformation indicating whether to allow accepting the data of the UE orUEs in the UE group beyond the network access time of the UE or UEgroup. Or the indication information indicating whether to allowaccepting the data of the UE or UEs in the UE group beyond the networkaccess time of the UE or UE group may be defined in the subscriptiondata. For example, the mobility management element learns from thesubscription data the indication information indicating whether to allowaccepting the data of the UE or UEs in the UE group beyond the networkaccess time of the UE or UE group, and then sends the indicationinformation indicating whether to allow accepting the data of the UE orUEs in the UE group beyond the network access time of the UE or UE groupto the gateway device through a session management request message.

The congestion/overload control method in this embodiment may be appliedin multiple radio access networks, for example, the Evolved UMTS(Universal Mobile Telecommunication System, UMTS) Terrestrial RadioAccess Network (Evolved UMTS Terrestrial Radio Access Network, E-UTRAN),UMTS Terrestrial Radio Access Network (UMTS Terrestrial Radio AccessNetwork, UTRAN), GSM (Global System for Mobile Communications) or EDGE(Enhanced Data rate for GSM Evolution, EDGE) Radio Access Network(GSM/EDGE Radio Access Network, GERAN), and non 3^(rd) GenerationPartner Project (3^(rd) Generation Partner Project, 3GPP) network.

The mobility management element may be a Mobility Management Entity(Mobility Management Entity, MME) in the E-UTRAN, or a Serving GPRS(General Packet Radio Service, GPRS) Supporting Node (Serving GPRSSupporting Node, SGSN) in the UTRAN/GERAN.

The gateway device may be a network element such as a Serving Gateway(Serving Gateway, S-GW), a Packet Data Network Gateway (Packet DataNetwork Gateway, P-GW), or a Gateway GPRS (General Packet Radio Service,GPRS) Supporting Node (Gateway GPRS Supporting Node, GGSN).

Similarly, the mobility management element in this embodiment may alsoperform congestion/overload control differentially on UEs in the groupin a similar way, which is not further described here. When the mobilitymanagement element is congested/overloaded, the mobility managementelement may perform congestion/overload control differentially on a UEor UEs in a UE group according to the learned information about thenetwork access time of the UE or UE group, so that congestion/overloadcontrol can be performed on the mobility management element,congestion/overload caused by a large number of UEs on the gatewaydevice is avoided, and the efficiency of congestion/overload control isimproved.

FIG. 2 is a schematic flowchart of a congestion/overload control methodaccording to a second embodiment of the present invention. Thisembodiment is a specific instance of the first embodiment. As shown inFIG. 2, the congestion/overload control method in this embodiment mayinclude the following steps:

Step 201: A UE sends an access request message to a mobility managementelement.

The access request message may be an Attach Request message, a RoutingArea Update Request message, a Tracking Area Update Request message, aService Request message, a PDN Connectivity Request message, or anActivate PDP Context Request message.

Step 202: The mobility management element receives the access requestmessage, and if the access request message is an Attach Request message,a Routing Area Update Request message, or a Tracking Area Update Requestmessage, sends an Update Location Request message to a subscriptionprofile repository.

Step 203: The subscription profile repository receives the UpdateLocation Request message, and returns an Update Location Ack message tothe mobility management element, where the Update Location Ack messagemay carry information about the network access time of the UE or UEgroup.

Step 204: The mobility management element receives the Update LocationAck message, and sends a session management request message to thegateway device, where the session management request message may carryinformation about the network access time of the UE or UE group.

The information about the network access time of the UE or UE groupcarried in the session management request message may be learned by themobility management element from the subscription profile repository orUE contexts, or may be configured by the mobility management elementitself.

The session management request message may be a Create PDP ContextRequest message, a Create Session Request message, or a Modify BearerRequest message.

If the gateway device is a PGW, the mobility management element may sendthe session management message to the PGW through the SGW.

Step 205: The gateway device receives the session management requestmessage, and returns a session management request response message tothe mobility management element. The gateway device performscongestion/overload control according to the information about thenetwork access time of the UE or UE group, where the information aboutthe network access time of the UE or UE group according to which thegateway device performs congestion/overload control may be learned fromthe mobility management element or configured by the gateway deviceitself.

The session management request response message may be a Create PDPContext Response/Reject message, a Create Session Response/Rejectmessage, or a Modify Bearer Response/Reject message.

In this step, the method for the gateway device to performcongestion/overload control is described in the first embodiment, andnot further described here.

Optionally, the gateway device may carry first time indicationinformation (back-off time) (for example, duration or time point) and/ora cause value in a session management request response message. Thefirst time indication information and/or cause value is described in thefirst embodiment, and not further described here.

Step 206: The mobility management element receives the sessionmanagement request response message, and returns an access requestresponse message to the UE or UEs in the UE group.

The access request response message may be an Attach Accept/Rejectmessage, a Routing Area Update Accept/Reject message, a Tracking AreaUpdate Accept/Reject message, a Service Request Accept/Reject message, aPDN Connectivity Accept/Reject message, or an Active PDP ContextAccept/Reject message.

Optionally, the mobility management element may carry second timeindication information (back-off time) (for example, duration or timepoint) and/or cause value information in the access request responsemessage. The second time indication information and/or cause valueinformation is described in the first embodiment, and not furtherdescribed here.

By using the congestion/overload control method provided in thisembodiment, when the gateway device is congested/overloaded, the gatewaydevice may perform congestion/overload control differentially on the UEor UEs in the UE group according to the learned information about thenetwork access time of the UE or UE group, so that congestion/overloadcontrol can be performed on the gateway device, congestion/overloadcaused by a large number of UEs on the gateway device is avoided, andthe efficiency of congestion/overload control is improved.

FIG. 3 is a schematic flowchart of another congestion/overload controlmethod according to a third embodiment of the present invention. Asshown in FIG. 3, the congestion/overload control method in thisembodiment may include the following steps:

Step 301: A gateway device learns information about acongestion/overload control parameter or policy of a UE group.

Step 302: If the congestion/overload control parameter or policy of theUE group is reached or exceeded,

the gateway device rejects or discards session management requestmessages of UEs in the UE group, or

discards data of the UEs in the UE group, or

deletes bearers or PDP contexts of the UEs in the UE group, or

discards data that exceeds the congestion/overload control parameter orpolicy of the UE group, or

charges for the data that exceeds the congestion/overload controlparameter or policy of the UE group.

By using the congestion/overload control method provided in thisembodiment, when the gateway device is congested/overloaded, the gatewaydevice may perform congestion/overload control differentially on the UEsin the UE group according to the learned information about thecongestion/overload control parameter or policy of the UE group, so thatcongestion/overload control can be performed on the gateway device,congestion/overload caused by a large number of UEs on the gatewaydevice is avoided, and the efficiency of congestion/overload control isimproved.

The information about the congestion/overload control parameter orpolicy of the UE group learned by the gateway device may include atleast one of the following parameters or policies:

maximum number of bearers or PDP contexts of the UE group;

maximum access rate of the UE group;

Aggregate Maximum Bit Rate (AMBR) of bearers of the UE group;

AMBR of Non Guaranteed Bit Rate (GBR) bearers of the UE group;

AMBR of bearers of the UE group in the same APN; and

AMBR of non-GBR bearers of the UE group in the same APN.

In step 301 of this embodiment, the gateway device may learn theinformation about the congestion/overload control parameter or policy ofthe UE group in the following modes:

A. Learn the information about the congestion/overload control parameteror policy of the UE group from a mobility management element.

Specifically, after learning the information about thecongestion/overload control parameter or policy of the UE group, themobility management element may send the information about thecongestion/overload control parameter or policy to the gateway devicethrough a session management message, for example, Create PDP ContextRequest message, or Create Session Request message. The mobilitymanagement element may learn the information about thecongestion/overload control parameter or policy in the following modes:

a. Learn the information about the congestion/overload control parameteror policy of the UE group from a subscription profile repository.

After receiving an access request message that is sent by the UE andcarries a UE ID or UE group ID, the mobility management element maylearn subscription data of the UE group from the subscription profilerepository such as a Home Location Register (Home Location Register,HLR) or a Home Subscriber Server (Home Subscriber Server, HSS) accordingto the UE ID or UE group ID, where the subscription data includes theinformation about the congestion/overload control parameter or policy ofthe UE group. The specific mode may be: the mobility management elementsends an Update Location Request message to the subscription profilerepository; after receiving the Update Location Request message, thesubscription profile repository returns the information about thecongestion/overload control parameter or policy of the UE group in thesubscription data to the mobility management element through an UpdateLocation Ack message.

The access request message may be an Attach Request message, a RoutingArea Update Request message, a Tracking Area Update Request message, aService Request message, a PDN Connectivity Request message, or anActivate PDP Context Request message.

b. Learn the information about the congestion/overload control parameteror policy of the UE group from UE contexts.

Specifically, if UE contexts are stored on the mobility managementelement, the mobility management element may also learn the informationabout the congestion/overload control parameter or policy of the UEgroup from the UE contexts.

c. Learn the information about the congestion/overload control parameteror policy of the UE group from configuration information.

The mobility management element may configure the information about thecongestion/overload control parameter or policy of the UE groupaccording to an ID of the UE group (referred to as a group ID), andlearn the information about the congestion/overload control parameter orpolicy of the UE group from the configuration information. The group IDis used to identify a group, and the group may be a UE group, a Machineto Machine (Machine to Machine, M2M) MTC user, an M2M applicationsubscriber (an MTC subscriber or an MTC server), or other groupsconsisting of multiple devices, which is not limited in this embodiment.The group ID above may be a UE group ID, or an ID shared by multiple UEsin a group, for example, an International Mobile SubscriberIdentification Number (International Mobile Subscriber IdentificationNumber, IMSI), a Mobile Station International Integrated ServicesDigital Network Number (Mobile Station International Integrated ServicesDigital Network Number, MSISDN), or an International Mobile EquipmentIdentity (International Mobile Equipment Identity, IMEI), or may also bean IMSI segment or an MSISDN segment, or may also be other IDs that canindicate a group, for example, an Access Point Name (Access Point Name,APN). This embodiment does not limit the form of the group ID.

B. Learn the information about the congestion/overload control parameteror policy of the UE group from configuration information.

The gateway device may configure the information about thecongestion/overload control parameter or policy of the UE groupaccording to an ID of the UE group (referred to as a group ID), andlearn the information about the congestion/overload control parameter orpolicy of the UE group from the configuration information. Specifically,the gateway device may learn the UE ID or UE group ID through a sessionmanagement message sent by the mobility management element, for example,Create PDP Context Request message, or Create Session Request message,and learn the information about the congestion/overload controlparameter or policy of the UE group from the configuration informationaccording to the UE ID or UE group ID.

C. Learn the information about the congestion/overload control parameteror policy of the UE group from a database.

The gateway device may learn the UE ID or UE group ID through a sessionmanagement message sent by the mobility management element, for example,Create PDP Context Request message, or Create Session Request message,and query a database such as an Authentication, Authorization andAccounting (Authentication, Authorization and Accounting, AAA) serverfor the information about the congestion/overload control parameter orpolicy of the UE group according to the UE ID or UE group ID.

In step 302 of this embodiment, if the number of bearers or PDP contextsof the UE group reaches or exceeds the maximum number of bearers or PDPcontexts of the UE group, the gateway device may performcongestion/overload control in the following modes:

A. Reject or discard session management request messages of UEs in theUE group.

Specifically, when the gateway device is in the congested/overloadedstate, if the gateway device receives the session management requestmessage sent by the mobility management element for the UEs in the UEgroup, for example, Create PDP Context Request message, Create SessionRequest message, or Modify Bearer Request message, the gateway devicerejects or discards the session management request message. Optionally,the gateway device may accept or reject or discard the sessionmanagement request message according to indication informationindicating whether the number of bearers or PDP contexts of the UE groupis allowed to reach or exceed the maximum number of bearers or PDPcontexts of the UE group. For example, if the indication informationindicates that the number of bearers or PDP contexts of the UE group isnot allowed to reach or exceed the maximum number of bearers or PDPcontexts of the UE group, the gateway device rejects or discards thesession management request message of the UEs in the group.

The indication information indicating whether the number of bearers orPDP contexts of the UE group is allowed to reach or exceed the maximumnumber of bearers or PDP contexts of the UE group may be configured onthe gateway device. For example, after receiving the session managementrequest message sent by the mobility management element, the gatewaydevice queries the configuration information according to the UE ID orUE group ID in the session management request message, and learns theindication information indicating whether the number of bearers or PDPcontexts of the UE group is allowed to reach or exceed the maximumnumber of bearers or PDP contexts of the UE group. Or the indicationinformation indicating whether the number of bearers or PDP contexts ofthe UE group is allowed to reach or exceed the maximum number of bearersor PDP contexts of the UE group may be defined in the subscription data.For example, the mobility management element learns from thesubscription data the indication information indicating whether thenumber of bearers or PDP contexts of the UE group is allowed to reach orexceed the maximum number of bearers or PDP contexts of the UE group,and then sends the indication information indicating whether the numberof bearers or PDP contexts of the UE group is allowed to reach or exceedthe maximum number of bearers or PDP contexts of the UE group to thegateway device through a session management request message.

Further, the gateway device may reject or discard, according to apercentage, the session management request message sent by the mobilitymanagement element for the UEs in the UE group. If the number of bearersor PDP contexts of the UE group reaches or exceeds the maximum number ofbearers or PDP contexts of the UE group, the gateway device receives thesession management request message sent by the mobility managementelement for the UEs in the UE group, and rejects or discards the sessionmanagement request message according to the percentage.

Optionally, the gateway device may also carry time indicationinformation (called first time indication information) (back-off time)(for example, duration or time point) and/or a cause value in a sessionmanagement reject message returned to the mobility management element.

After receiving the first time indication information and/or causevalue, the mobility management element may perform the followingprocessing:

1. The mobility management element sends the first time indicationinformation and/or cause value to the UE (for example, the mobilitymanagement element sends the first time indication information and/orcause value to the UE through an access request reject message). Or

2. The mobility management element generates time indication information(called second time indication information) and/or cause valueinformation according to the received first time indication informationand/or cause value, and sends the generated second time indicationinformation and/or cause value information to the UE. For example, afterlearning the first time indication information sent by the gatewaydevice, the mobility management element receives an access request sentby the UE, subtracts the time point of receiving the access request sentby the UE from the first time indication information, and uses theobtained result as the value of the second time indication information.Or

3. The mobility management element performs access control (for example,rejects or discards the access request message of the UE) according tothe first time indication information and/or cause value. Specifically,the first time indication information may be used to instruct themobility management element to reject or discard the access requestmessage of the UEs in the UE group within the time range indicated bythe first time indication information (for example, before the firsttime indication information expires); or the first time indicationinformation may be used to instruct the mobility management element toaccept the access request message of the UEs in the UE group beyond thetime range indicated by the first time indication information (forexample, after the first time indication information expires); the causevalue may be used to notify the mobility management element that thegateway device is in the congested/overloaded state. Or

4. The mobility management element performs access control according tothe first time indication information and/or cause value (described in3), and sends the first time indication information and/or cause valueto the UE (for example, the mobility management element sends the firsttime indication information and/or cause value to the UE through anaccess request reject message).

In addition, after receiving the session reject request message of thegateway device, the mobility management element may generate (provide)the second time indication information and/or cause value information,and send the second time indication information and/or cause valueinformation to the UE (for example, the mobility management elementsends the second time indication information and/or cause valueinformation to the UE through an access request reject message). Forexample, the mobility management element generates second timeindication information and/or cause value information according toconfiguration information (the value of the second time indicationinformation configured on the mobility management element).

The second time indication information sent by the mobility managementelement to the UE is used to instruct the UE not to initiate an accessrequest frequently or immediately. Specifically, the second timeindication information may be used to instruct the UEs in the UE groupnot to send access request messages within the time range indicated bythe second time indication information (for example, before the secondtime indication information expires); or the second time indicationinformation may also be used to instruct the UEs in the UE group to sendaccess request messages beyond the time range indicated by the secondtime indication information (for example, after the second timeindication information expires); the cause value information may befurther used to instruct the UEs in the UE group not to send accessrequest messages frequently or immediately. According to the second timeindication information and/or cause value information sent by themobility management element to the UE, the UE will not initiate anaccess request frequently or immediately, which reduces the frequent andrepeated signaling impact caused by a large number of UEs on thenetwork, and avoids network congestion or overload caused by the impactof a large amount of signaling.

B. Discard data of the UEs in the UE group.

Specifically, when the gateway device is in the congested/overloadedstate, if the gateway device receives the data of the UEs in the UEgroup, the gateway device discards the data. For example, the gatewaydevice may set the bearer gate status of the UEs in the UE group toclosed; when the gateway device receives the data of the UEs in the UEgroup, the gateway device may discard the data. Optionally, the gatewaydevice may discard the data of the UEs in the UE group according to theindication information indicating whether the number of bearers or PDPcontexts of the UE group is allowed to reach or exceed the maximumnumber of bearers or PDP contexts of the UE group. For example, if theindication information indicates that the number of bearers or PDPcontexts of the UE group is not allowed to reach or exceed the maximumnumber of bearers or PDP contexts of the UE group, the gateway devicediscards the data of the UEs in the UE group. The method for the gatewaydevice to learn the indication information indicating whether the numberof bearers or PDP contexts of the UE group is allowed to reach or exceedthe maximum number of bearers or PDP contexts of the UE group isdescribed in A.

C. Delete bearers or PDP contexts of the UEs in the UE group.

Specifically, the gateway device may initiate a bearer deletionprocedure to delete the bearers or PDP contexts of the UEs in the UEgroup. Optionally, the gateway device may discard the data of the UEs inthe UE group according to the indication information indicating whetherthe number of bearers or PDP contexts of the UE group is allowed toreach or exceed the maximum number of bearers or PDP contexts of the UEgroup. For example, if the indication information indicates that thenumber of bearers or PDP contexts of the UE group is not allowed toreach or exceed the maximum number of bearers or PDP contexts of the UEgroup, the gateway device deletes the bearers or PDP contexts of the UEsin the UE group. The method for the gateway device to learn theindication information indicating whether the number of bearers or PDPcontexts of the UE group is allowed to reach or exceed the maximumnumber of bearers or PDP contexts of the UE group is described in A.

In step 302 of this embodiment, if the access rate of the UE group (rateof sending access requests by the UEs in the UE group, for example, therate of sending Attach Requests, PDN Connectivity Requests, or ActivatePDP Context Requests by the UEs in the UE group) reaches or exceeds themaximum access rate of the UE group (the maximum rate of sending accessrequests by the UEs in the UE group, for example, the maximum rate ofsending Attach Requests, PDN Connectivity Requests, or Activate PDPContext Requests by the UEs in the UE group), the gateway device mayperform congestion/overload control in the following modes:

A. Reject or discard session management request messages of the UEs inthe UE group.

Specifically, when the gateway device is in the congested/overloadedstate, if the gateway device receives the session management requestmessage sent by the mobility management element for the UEs in the UEgroup, for example, Create PDP Context Request message, Create SessionRequest message, or Modify Bearer Request message, the gateway devicerejects or discards the session management request message. Optionally,the gateway device may accept or reject or discard the sessionmanagement request message according to indication informationindicating whether the access rate of the UE group is allowed to reachor exceed the maximum access rate of the UE group. For example, if theindication information indicates the access rate of the UE group is notallowed to reach or exceed the maximum access rate of the UE group, thegateway device rejects or discards the session management requestmessage of the UEs in the UE group.

The indication information indicating whether the access rate of the UEgroup is allowed to reach or exceed the maximum access rate of the UEgroup may be configured on the gateway device. For example, afterreceiving the session management request message sent by the mobilitymanagement element, the gateway device queries the configurationinformation according to the UE ID or UE group ID in the sessionmanagement request message, and learns the indication informationindicating whether the access rate of the UE group is allowed to reachor exceed the maximum access rate of the UE group. Or the indicationinformation indicating whether the access rate of the UE group isallowed to reach or exceed the maximum access rate of the UE group maybe defined in the subscription data. For example, the mobilitymanagement element learns from the subscription data the indicationinformation indicating whether the access rate of the UE group isallowed to reach or exceed the maximum access rate of the UE group, andthen sends the indication information indicating whether the access rateof the UE group is allowed to reach or exceed the maximum access rate ofthe UE group to the gateway device through a session management requestmessage.

Further, the gateway device may reject or discard, according to apercentage, the session management request message sent by the mobilitymanagement element for the UEs in the UE group. If the access rate ofthe UE group reaches or exceeds the maximum access rate of the UE group,the gateway device receives the session management request message sentby the mobility management element for the UEs in the UE group, andrejects or discards the session management request message according tothe percentage.

Optionally, the gateway device may also carry time indicationinformation (called first time indication information) (back-off time)(for example, duration or time point) and/or a cause value in a sessionmanagement reject message returned to the mobility management element.

After receiving the first time indication information and/or causevalue, the mobility management element may perform the followingprocessing:

1. The mobility management element sends the first time indicationinformation and/or cause value to the UE (for example, the mobilitymanagement element sends the first time indication information and/orcause value to the UE through an access request reject message). Or

2. The mobility management element generates time indication information(called second time indication information) and/or cause valueinformation according to the received first time indication informationand/or cause value, and sends the generated second time indicationinformation and/or cause value information to the UE. For example, afterlearning the first time indication information sent by the gatewaydevice, the mobility management element receives an access request sentby the UE, subtracts the time point of receiving the access request sentby the UE from the first time indication information, and uses theobtained result as the value of the second time indication information.Or

3. The mobility management element performs access control (for example,rejects or discards the access request message of the UE) according tothe first time indication information and/or cause value. Specifically,the first time indication information may be used to instruct themobility management element to reject or discard the access requestmessage of the UEs in the UE group within the time range indicated bythe first time indication information (for example, before the firsttime indication information expires); or the first time indicationinformation may be used to instruct the mobility management element toaccept the access request message of the UEs in the UE group beyond thetime range indicated by the first time indication information (forexample, after the first time indication information expires); the causevalue may be used to notify the mobility management element that thegateway device is in the congested/overloaded state. Or

4. The mobility management element performs access control according tothe first time indication information and/or cause value (described in3), and sends the first time indication information and/or cause valueto the UE (for example, the mobility management element sends the firsttime indication information and/or cause value to the UE through anaccess request reject message).

In addition, after receiving the session reject request message of thegateway device, the mobility management element may generate (provide)the second time indication information and/or cause value information,and send the second time indication information and/or cause valueinformation to the UE (for example, the mobility management elementsends the second time indication information and/or cause valueinformation to the UE through an access request reject message). Forexample, the mobility management element generates second timeindication information and/or cause value information according toconfiguration information (the value of the second time indicationinformation configured on the mobility management element).

The second time indication information sent by the mobility managementelement to the UE is used to instruct the UE not to initiate an accessrequest frequently or immediately. Specifically, the second timeindication information may be used to instruct the UEs in the UE groupnot to send access request messages within the time range indicated bythe second time indication information (for example, before the secondtime indication information expires); or the second time indicationinformation may also be used to instruct the UEs in the UE group to sendaccess request messages beyond the time range indicated by the secondtime indication information (for example, after the second timeindication information expires); the cause value information may befurther used to instruct the UEs in the UE group not to send accessrequest messages frequently or immediately. According to the second timeindication information and/or cause value information sent by themobility management element to the UE, the UE will not initiate anaccess request frequently or immediately, which reduces the frequent andrepeated signaling impact caused by a large number of UEs on thenetwork, and avoids network congestion or overload caused by the impactof a large amount of signaling.

B. Discard data of the UEs in the UE group.

Specifically, when the gateway device is in the congested/overloadedstate, if the gateway device receives the data of the UEs in the UEgroup, the gateway device discards the data. For example, the gatewaydevice may set the bearer gate status of the UEs in the UE group toclosed; when the gateway device receives the data of the UEs in the UEgroup, the gateway device may discard the data.

In step 302 of this embodiment, the gateway device limits the totalbandwidth (aggregate bit rate) of bearers of the UE group according tothe AMBR of bearers of the UE group, or limits the total bandwidth ofnon-GBR bearers of the UE group according to the AMBR of non-GBR bearersof the UE group, or limits the total bandwidth of bearers of the UEgroup in the same APN according to the AMBR of bearers of the UE groupin the same APN, or limits the total bandwidth (aggregate bit rate) ofnon-GBR bearers of the UE group in the same APN according to the AMBR ofnon-GBR bearers of the UE group in the same APN (Group-APN-AMBR). If thetotal bandwidth (bit rate) of bearers of the UE group reaches or exceedsthe AMBR of the bearers of the UE group, or if the total bandwidth ofnon-GBR bearers of the UE group reaches or exceeds the AMBR of non-GBRbearers of the UE group, or if the total bandwidth of bearers of the UEgroup in the same APN reaches or exceeds the AMBR of bearers of the UEgroup in the same APN, or if the total bandwidth of non-GBR bearers ofthe UE group in the same APN reaches or exceeds the AMBR of non-GBRbearers of the UE group in the same APN, the gateway device may performcongestion/overload control in the following modes:

A. Discard the data that exceeds the AMBR; or

B. Charge for the data that exceeds the AMBR.

The congestion/overload control method in this embodiment may be appliedin multiple radio access networks, for example, the Evolved UMTS(Universal Mobile Telecommunication System, UMTS) Terrestrial RadioAccess Network (Evolved UMTS Terrestrial Radio Access Network, E-UTRAN),UMTS Terrestrial Radio Access Network (UMTS Terrestrial Radio AccessNetwork, UTRAN), GSM (Global System for Mobile Communications) or EDGE(Enhanced Data rate for GSM Evolution, EDGE) Radio Access Network(GSM/EDGE Radio Access Network, GERAN), and non 3^(rd) GenerationPartner Project (3^(rd) Generation Partner Project, 3GPP) network.

The mobility management element may be a Mobility Management Entity(Mobility Management Entity, MME) in the E-UTRAN, or a Serving GPRS(General Packet Radio Service, GPRS) Supporting Node (Serving GPRSSupporting Node, SGSN) in the UTRAN/GERAN.

The gateway device may be a network element such as a Serving Gateway(Serving Gateway, S-GW), a Packet Data Network Gateway (Packet DataNetwork Gateway, P-GW), or a Gateway GPRS (General Packet Radio Service,GPRS) Supporting Node (Gateway GPRS Supporting Node, GGSN).

Similarly, the mobility management element in this embodiment may alsoperform congestion/overload control differentially on UEs in the groupin a similar way; the only difference is: the information about thecongestion/overload control parameter or policy of the UE group learnedby the mobility management element may at least include the maximumnumber of bearers or PDP contexts of the UE group and/or the maximumaccess rate of the UE group, which is not further described here. Whenthe mobility management element is congested/overloaded, the mobilitymanagement element may perform congestion/overload controldifferentially on UEs in a UE group according to the learned informationabout the congestion/overload control parameter or policy of the UEgroup, so that congestion/overload control can be performed on themobility management element, congestion/overload caused by a largenumber of UEs on the gateway device is avoided, and the efficiency ofcongestion/overload control is improved.

FIG. 4 is a schematic flowchart of another congestion/overload controlmethod according to a fourth embodiment of the present invention. Thisembodiment is a specific instance of the third embodiment. As shown inFIG. 4, the congestion/overload control method in this embodiment mayinclude the following steps:

Step 401: A UE sends an access request message to a mobility managementelement.

The access request message may be an Attach Request message, a RoutingArea Update Request message, a Tracking Area Update Request message, aService Request message, a PDN Connectivity Request message, or anActivate PDP Context Request message.

Step 402: The mobility management element receives the access requestmessage, and if the access request message is an Attach Request message,a Routing Area Update Request message, or a Tracking Area Update Requestmessage, sends an Update Location Request message to a subscriptionprofile repository.

Step 403: The subscription profile repository receives the UpdateLocation Request message, and returns an Update Location Ack message tothe mobility management element, where the Update Location Ack messagemay carry the information about the congestion/overload controlparameter or policy of the UE group.

Step 404: The mobility management element receives the Update LocationAck message, and sends a session management request message to thegateway device, where the session management request message may carrythe information about the congestion/overload control parameter orpolicy of the UE group.

The information about the congestion/overload control parameter orpolicy of the UE group carried in the session management request messagemay be learned by the mobility management element from the subscriptionprofile repository or UE contexts, or may be configured by the mobilitymanagement element itself.

The session management request message may be a Create PDP ContextRequest message, a Create Session Request message, or a Modify BearerRequest message.

If the gateway device is a PGW, the mobility management element may sendthe session management message to the PGW through an SGW.

Step 405: The gateway device receives the session management requestmessage, and returns a session management request response message tothe mobility management element. The gateway device performscongestion/overload control according to the information about thecongestion/overload control parameter or policy of the UE group, wherethe information about the congestion/overload control parameter orpolicy of the UE group according to which the gateway device performscongestion/overload control may be learned from the mobility managementelement or configured by the gateway device itself.

The session management request response message may be a Create PDPContext Response/Reject message, a Create Session Response/Rejectmessage, or a Modify Bearer Response/Reject message.

In this step, the method for the gateway device to performcongestion/overload control is described in the third embodiment, andnot further described here.

Optionally, the gateway device may carry first time indicationinformation (back-off time) (for example, duration or time point) and/ora cause value in a session management request response message. Thefirst time indication information and/or cause value is described in thethird embodiment, and not further described here.

Step 406: The mobility management element receives the sessionmanagement request response message, and returns an access requestresponse message to the UE or UEs in the UE group.

The access request response message may be an Attach Accept/Rejectmessage, a Routing Area Update Accept/Reject message, a Tracking AreaUpdate Accept/Reject message, a Service Request Accept/Reject message, aPDN Connectivity Accept/Reject message, or an Active PDP ContextAccept/Reject message.

Optionally, the mobility management element may carry second timeindication information (back-off time) (for example, duration or timepoint) and/or cause value information in the access request responsemessage. The second time indication information and/or cause valueinformation is described in the first embodiment, and not furtherdescribed here.

By using the congestion/overload control method provided in thisembodiment, when the gateway device is congested/overloaded, the gatewaydevice may perform congestion/overload control differentially on the UEsin the UE group according to the learned information about thecongestion/overload control parameter or policy of the UE group, so thatcongestion/overload control can be performed on the gateway device,congestion/overload caused by a large number of UEs on the gatewaydevice is avoided, and the efficiency of congestion/overload control isimproved.

FIG. 5 is a schematic flowchart of still another congestion/overloadcontrol method according to a fifth embodiment of the present invention.As shown in FIG. 5, the congestion/overload control method in thisembodiment may include the following steps:

Step 501: Receive an indication message sent by a gateway device, wherethe indication message indicates that the gateway device iscongested/overloaded or that an application server isfailed/congested/overloaded/unreachable/misbehaving.

Step 502: Select other gateway devices for UEs that access the gatewaydevice; or

reject or discard access request messages of UEs served by the gatewaydevice or the application server; or

detach UEs on the gateway device or the application server; or

delete bearers of the UEs on the gateway device or the applicationserver.

By using the congestion/overload control method provided in thisembodiment, when the gateway device is congested/overloaded or theapplication server isfailed/congested/overloaded/unreachable/misbehaving, the mobilitymanagement element may perform congestion/overload control according tothe indication message sent by the gateway device, so thatcongestion/overload control can be performed on the gateway device, andcongestion/overload caused by a large number of UEs on the gatewaydevice is avoided.

In step 501 of this embodiment, when the gateway device is in thecongested/overloaded state or the application server (MTC server) is inthe failed/congested/overloaded/unreachable/misbehaving state, thegateway device sends an indication message to the mobility managementelement, notifying the mobility management element that the gatewaydevice is congested/overloaded or that the application server isfailed/congested/overloaded/unreachable/misbehaving, and the mobilitymanagement element performs congestion/overload control. Optionally, theindication message may carry the group ID of the group. For example, thegroup ID may identify the group that causes congestion/overload of thegateway device, the group served by thefailed/congested/overloaded/unreachable/misbehaving application serveror congested/overloaded gateway device, or the group that causes theapplication server to befailed/congested/overloaded/unreachable/misbehaving. The group ID isused to identify a group, and the group may be a UE group, a Machine toMachine (Machine to Machine, M2M) MTC user, an M2M applicationsubscriber (an MTC subscriber or an MTC server), or other groupsconsisting of multiple devices, which is not limited in this embodiment.The group ID above may be a UE group ID, or an ID shared by multiple UEsin a group, for example, an International Mobile SubscriberIdentification Number (International Mobile Subscriber IdentificationNumber, IMSI), a Mobile Station International Integrated ServicesDigital Network Number (Mobile Station International Integrated ServicesDigital Network Number, MSISDN), or an International Mobile EquipmentIdentity (International Mobile Equipment Identity, IMEI), or may also bean IMSI segment or an MSISDN segment, or may also be other IDs that canindicate a group, for example, an Access Point Name (Access Point Name,APN). This embodiment does not limit the form of the group ID.

Optionally, the indication message may carry parameter information,where the parameter information includes first time indicationinformation and/or a cause value.

Optionally, the gateway device may also perform congestion/overloadcontrol. The gateway device may discard the data of UEs in the followinggroup: the group that causes congestion/overload of the gateway device,the group served by thefailed/congested/overloaded/unreachable/misbehaving application serveror congested/overloaded gateway device, or the group that causes theapplication server to befailed/congested/overloaded/unreachable/misbehaving. For example, thegateway device may set the bearer gate status of the UEs in the UE groupto closed; when the gateway device receives the data of the UEs in theUE group, the gateway device may discard the data. The gateway devicemay delete the bearers of UEs in the following group: the group thatcauses congestion/overload of the gateway device, the group served bythe failed/congested/overloaded/unreachable/misbehaving applicationserver or congested/overloaded gateway device, or the group that causesthe application server to befailed/congested/overloaded/unreachable/misbehaving. For example, thegateway device initiates a bearer deletion procedure to delete thebearers of the UEs in the group.

In step 502 of this embodiment, the mobility management element learnsthat the gateway device is in the congested/overloaded state or that theapplication server is in thefailed/congested/overloaded/unreachable/misbehaving state according tothe learned indication message sent by the gateway device, and mayperform congestion/overload control in the following modes:

A. Select other gateway devices for UEs that access the gateway device.

Specifically, after receiving the access request message sent by the UE,the mobility management element may select other gateway devices for theUE. For example, the mobility management element learns a gateway devicelist for the UE according to the APN, and selects other gateway devicesfrom the gateway device list. If the indication message sent by thegateway device in step 501 carries the group ID of the group, themobility management element may select other gateway devices for the UEsin the group. Specifically, after receiving the access request messagesthat are sent by the UEs in the group and carry the UE ID or group ID,the mobility management element may select other gateway devices for theUEs. For example, the mobility management element learns a gatewaydevice list for the UEs in the group according to the APN, and selectsother gateway devices from the gateway device list. The access requestmessage may be an Attach Request message, a Routing Area Update Requestmessage, a Tracking Area Update Request message, a Service Requestmessage, a PDN Connectivity Request message, or an Activate PDP ContextRequest message.

B. Reject or discard access request messages of UEs served by thegateway device or the application server.

Specifically, the mobility management element receives the accessrequest message sent by a UE served by the gateway device or theapplication server, and rejects or discards the access request. Forexample, the UE carries an APN in the access request; if the APN targetsthe gateway device or application server, the mobility managementelement rejects or discards the access request of the UE. If theindication message sent by the gateway device in step 501 carries thegroup ID of the group, the mobility management element receives theaccess request message sent by the UEs in the group, and the mobilitymanagement element rejects or discards the access request message. Forexample, when the access request message carries a UE ID or group ID, ifthe UE ID belongs to (or is included in) the group ID in the indicationmessage (namely, the UE belongs to the group identified by the group IDin the indication message), or if the group ID is the same as the groupID in the indication message, the mobility management element rejects ordiscards the access request message of the UE.

Further, if the indication message received by the mobility managementelement carries time indication information (called first timeindication information) and/or a cause value, the mobility managementelement may perform the following processing after receiving the firsttime indication information and/or cause value:

1. The mobility management element sends the first time indicationinformation and/or cause value to the UE (for example, the mobilitymanagement element sends the first time indication information and/orcause value to the UE through an access request reject message). Or

2. The mobility management element generates time indication information(called second time indication information) and/or cause valueinformation according to the received first time indication informationand/or cause value, and sends the generated second time indicationinformation and/or cause value information to the UE. For example, afterlearning the first time indication information sent by the gatewaydevice, the mobility management element receives an access request sentby the UE, subtracts the time point of receiving the access request sentby the UE from the first time indication information, and uses theobtained result as the value of the second time indication information.Or

3. The mobility management element performs access control (for example,rejects or discards the access request message of the UE) according tothe first time indication information and/or cause value. Specifically,the mobility management element may reject or discard the access requestmessage of the UE within the time range indicated by the first timeindication information (for example, before the first time indicationinformation expires); or the mobility management element may also acceptthe access request message of the UE beyond the time range indicated bythe first time indication information (for example, after the first timeindication information expires); or according to the cause value, themobility management element may also learn that the gateway device is inthe congested/overloaded state or that the application server is in thefailed/congested/overloaded/unreachable/misbehaving state. Or

4. The mobility management element performs access control according tothe first time indication information and/or cause value (described in3), and sends the first time indication information and/or cause valueto the UE (for example, the mobility management element sends the firsttime indication information and/or cause value to the UE through anaccess request reject message).

In addition, after receiving the session reject request message of thegateway device, the mobility management element may generate (provide)the second time indication information and/or cause value information,and send the second time indication information and/or cause valueinformation to the UE (for example, the mobility management elementsends the second time indication information and/or cause valueinformation to the UE through an access request reject message). Forexample, the mobility management element generates second timeindication information and/or cause value information according toconfiguration information (the value of the second time indicationinformation configured on the mobility management element).

The second time indication information sent by the mobility managementelement to the UE is used to instruct the UE not to initiate an accessrequest frequently or immediately. Specifically, the second timeindication information may be used to instruct the UE not to send anaccess request message within the time range indicated by the secondtime indication information (for example, before the second timeindication information expires); or the second time indicationinformation is used to instruct the UE to send an access request messagebeyond the time range indicated by the second time indicationinformation (for example, after the second time indication informationexpires); the cause value information is used to instruct the UE not tosend an access request message frequently or immediately. According tothe second time indication information and/or cause value informationsent by the mobility management element to the UE, the UE will notinitiate an access request frequently or immediately, which reduces thefrequent and repeated signaling impact caused by a large number of UEson the network, and avoids network congestion or overload caused by theimpact of a large amount of signaling.

C. Detach UEs on the gateway device or the application server.

The mobility management element may initiate a detach procedure for theUE. For example, the mobility management element learns the UE to bedetached according to the information about the gateway device in the UEcontext (for example, the address of the gateway device) or informationabout the application server (or information about the gateway device orapplication server corresponding to the UE context, for example, anAPN), and initiates a detach procedure for the UE. If the indicationmessage sent by the gateway device in step 501 carries the group ID ofthe group, the mobility management element learns the UEs to be detachedin the group according to the group ID carried in the indicationmessage, and initiates a detach procedure for the UEs in the group.

D. Delete bearers of the UEs on the gateway device or the applicationserver.

The mobility management element may initiate a bearer deletion procedurefor the UE. For example, the mobility management element learns the UEwhose bearers need to be deleted according to the information about thegateway device in the UE context (for example, the address of thegateway device) or information about the application server (orinformation about the gateway device or application server correspondingto the gateway device, for example, an APN), and initiates a bearerdeletion procedure for the UE. If the indication message sent by thegateway device in step 501 carries the group ID of the group, themobility management element learns the UEs whose bearers need to bedeleted in the group according to the group ID carried in the receivedindication message, and initiates a bearer deletion procedure for theUEs in the group.

By using the congestion/overload control method provided in thisembodiment, when the gateway device is congested/overloaded or theapplication server isfailed/congested/overloaded/unreachable/misbehaving, the mobilitymanagement element may perform congestion/overload controldifferentially on a UE or UEs in a group according to the indicationmessage sent by the gateway device or the carried group ID or parameterinformation; further, the mobility management element may perform accesscontrol on the UE or UEs in the group within a duration according to theparameter information in the indication message, and the second timeindication information and/or cause value sent by the mobilitymanagement element to the UE instructs the UE not to send an accessrequest frequently or immediately, which reduces the frequent andrepeated signaling impact caused by a large number of UEs on thenetwork, and avoids network congestion or overload caused by the impactof a large amount of signaling. Under the control of the mobilitymanagement element, congestion/overload control can be implemented onthe gateway device, the congestion/overload caused by a large number ofUEs on the gateway device is avoided, and the efficiency ofcongestion/overload control is improved.

The congestion/overload control method in this embodiment may be appliedin multiple radio access networks, for example, the Evolved UMTS(Universal Mobile Telecommunication System, UMTS) Terrestrial RadioAccess Network (Evolved UMTS Terrestrial Radio Access Network, E-UTRAN),UMTS Terrestrial Radio Access Network (UMTS Terrestrial Radio AccessNetwork, UTRAN), GSM (Global System for Mobile Communications) or EDGE(Enhanced Data rate for GSM Evolution, EDGE) Radio Access Network(GSM/EDGE Radio Access Network, GERAN), and non 3^(rd) GenerationPartner Project (3^(rd) Generation Partner Project, 3GPP) network.

The mobility management element may be a Mobility Management Entity(Mobility Management Entity, MME) in the E-UTRAN, or a Serving GPRS(General Packet Radio Service, GPRS) Supporting Node (Serving GPRSSupporting Node, SGSN) in the UTRAN/GERAN.

The gateway device may be a network element such as a Serving Gateway(Serving Gateway, S-GW), a Packet Data Network Gateway (Packet DataNetwork Gateway, P-GW), or a Gateway GPRS (General Packet Radio Service,GPRS) Supporting Node (Gateway GPRS Supporting Node, GGSN).

FIG. 6 is a schematic flowchart of still another congestion/overloadcontrol method according to a sixth embodiment of the present invention.This embodiment is a specific instance of the fifth embodiment. As shownin FIG. 6, the congestion/overload control method in this embodiment mayinclude the following steps:

Step 601: A gateway device sends an indication message to a mobilitymanagement element, where the indication message is used to instruct themobility management element to perform congestion/overload control.

Specifically, when the gateway device is in the congested/overloadedstate, or the gateway device learns that the application server is inthe failed/congested/overloaded/unreachable/misbehaving state, thegateway device sends an indication message to the mobility managementelement, instructing the mobility management element to performcongestion/overload control (for example, reject or discard the accessrequest of the UE).

Optionally, the indication message may carry the group ID of the group,for example IDs such as an APN, IMSI segment, or MSISDN segment. Thegroup ID may identify the group that causes congestion/overload of thegateway device, the group served by thefailed/congested/overloaded/unreachable/misbehaving application serveror congested/overloaded gateway device, or the group that causes theapplication server to befailed/congested/overloaded/unreachable/misbehaving.

Optionally, the indication message may also carry first time indicationinformation and/or a cause value.

The first time indication information and/or cause value is described inthe fifth embodiment, and not further described here.

Step 602: The mobility management element receives the indicationmessage and returns an indication Ack message to the gateway device.

This step is optional.

Step 603: A UE sends an access request message to the mobilitymanagement element.

Step 604: The mobility management element rejects or discards the accessrequest message.

Specifically, the mobility management element receives the accessrequest message sent by the UE served by the gateway device or theapplication server, and rejects or discards the access request. Forexample, the UE carries an APN in the access request; if the APN targetsthe gateway device or application server, the mobility managementelement rejects or discards the access request of the UE. If theindication message sent by the gateway device in step 601 carries thegroup ID of the group, and if the access request message comes from theUE in the group, the mobility management element rejects or discards theaccess request message. For example, if the UE ID carried in the accessrequest message belongs to (or is included in) the group ID in theindication message (namely, the UE belongs to the group identified bythe group ID in the indication message), or if the group ID carried inthe access request message is the same as the group ID in the indicationmessage, the mobility management element rejects or discards the accessrequest message. Further, the mobility management element may carrysecond time indication information and/or cause value information in anaccess request reject message sent by the UE in the group.

The second time indication information and/or cause value in this stepis described in the fifth embodiment, and not further described here.

By using the congestion/overload control method provided in thisembodiment, when the gateway device is congested/overloaded or theapplication server isfailed/congested/overloaded/unreachable/misbehaving, the mobilitymanagement element may perform congestion/overload controldifferentially on a UE or UEs in a UE group according to the indicationmessage sent by the gateway device, so that congestion/overload controlcan be performed on the gateway device, congestion/overload caused by alarge number of UEs on the gateway device is avoided, and the efficiencyof congestion/overload control is improved.

It should be noted that, for ease of description, the foregoingembodiments of the present invention are all described as a series ofactions. Persons skilled in the art understand that the presentinvention is not limited to the sequence of actions described herein andthat according to the present invention, some steps may be performed inother sequence or at the same time. In addition, it is understandable topersons skilled in the art that the embodiments in the specification areexemplary embodiments and that actions and modules involved in theseembodiments are not mandatory for the present invention.

In the foregoing embodiments of the present invention, each embodimenthas its emphasis. What is not detailed in one embodiment of the presentinvention is detailed in the related description of another embodiment.

FIG. 7 is a schematic structural diagram of a gateway device accordingto a seventh embodiment of the present invention. As shown in FIG. 7,the gateway device in this embodiment may include a learning module 71and a controlling module 72. The learning module 71 learns informationabout the network access time of a UE or UE group, and the controllingmodule 72 rejects or discards session management request messages of theUE or UEs in the UE group or discards data of the UE or UEs in the UEgroup beyond the network access time of the UE or UE group.

Both the method in the first embodiment and the function of the gatewaydevice in the second embodiment may be implemented by the gateway deviceprovided in this embodiment.

With the gateway device provided in this embodiment, when the gatewaydevice is congested/overloaded, the controlling module may performcongestion/overload control differentially on the UE or UEs in the groupaccording to the learned information about the network access time ofthe UE or UE group, so that congestion/overload control can be performedon the gateway device, congestion/overload caused by a large number ofUEs on the gateway device is avoided, and the efficiency ofcongestion/overload control is improved.

Further, specifically, the learning module 71 in this embodiment maylearn information about the network access time of the UE or UE groupfrom a mobility management element through a session management message,where the information about the network access time of the UE or UEgroup is learned by the mobility management element from configurationinformation; or learn information about the network access time of theUE or UE group from a mobility management element through a sessionmanagement message, where the information about the network access timeof the UE or UE group is learned by the mobility management element froma subscription profile repository; or learn information about thenetwork access time of the UE or UE group from a mobility managementelement through a session management message, where the informationabout the network access time of the UE or UE group is learned by themobility management element from UE contexts; or learn information aboutthe network access time of the UE or UE group from configurationinformation of the gateway device; or learn information about thenetwork access time of the UE or UE group from a database.

Further, if the controlling module 72 in this embodiment rejects thesession management request message of the UE or UEs in the UE group, thecontrolling module 72 may send a session management reject message tothe mobility management element, where the session management rejectmessage carries time indication information (called first timeindication information) and/or a cause value, where:

the first time indication information is used to instruct the mobilitymanagement element to reject or discard the access request message ofthe UE or UEs in the UE group within the time range indicated by thefirst time indication information; or

the first time indication information is used to instruct the mobilitymanagement element to accept the access request message of the UE or UEsin the UE group beyond the time range indicated by the first timeindication information; or

the cause value is used to notify the mobility management element thatthe gateway device is in the congested/overloaded state.

FIG. 8 is a schematic structural diagram of another gateway deviceaccording to an eighth embodiment of the present invention. As shown inFIG. 8, the gateway device in this embodiment may include a learningmodule 81 and a controlling module 82. The learning module 81 learnsinformation about a congestion/overload control parameter or policy of aUE group, and when the congestion/overload control parameter or policyof the UE group is reached or exceeded, the controlling module 82rejects or discards the session management request message of UEs in theUE group, or discards data of the UEs in the UE group, or deletesbearers or PDP contexts of the UEs in the UE group, or discards the datathat exceeds the congestion/overload control parameter or policy of theUE group, or charges for the data that exceeds the congestion/overloadcontrol parameter or policy of the UE group.

Both the method in the third embodiment and the function of the gatewaydevice in the fourth embodiment may be implemented by the gateway deviceprovided in this embodiment.

With the gateway device provided in this embodiment, when the gatewaydevice is congested/overloaded, the controlling module may performcongestion/overload control differentially on the UEs in the groupaccording to the information about the congestion/overload controlparameter or policy of the UE group learned by the learning module, sothat congestion/overload control can be performed on the gateway device,congestion/overload caused by a large number of UEs on the gatewaydevice is avoided, and the efficiency of congestion/overload control isimproved.

Further, specifically, the learning module 81 in this embodiment maylearn the information about the congestion/overload control parameter orpolicy of the UE group from a mobility management element through asession management message, where the information about thecongestion/overload control parameter or policy of the UE group islearned by the mobility management element from configurationinformation; or learn the information about the congestion/overloadcontrol parameter or policy of the UE group from a mobility managementelement through a session management message, where the informationabout the congestion/overload control parameter or policy of the UEgroup is learned by the mobility management element from a subscriptionprofile repository; or learn the information about thecongestion/overload control parameter or policy of the UE group from amobility management element through a session management message, wherethe information about the congestion/overload control parameter orpolicy of the UE group is learned by the mobility management elementfrom UE contexts; or learn the information about the congestion/overloadcontrol parameter or policy of the UE group from configurationinformation of the gateway device; or learn the information about thecongestion/overload control parameter or policy of the UE group from adatabase.

The information about the congestion/overload control parameter orpolicy of the UE group in this embodiment includes at least one of thefollowing parameters or policies:

maximum number of bearers or PDP contexts of the UE group;

maximum access rate of the UE group;

AMBR of bearers of the UE group;

AMBR of non-GBR bearers of the UE group;

AMBR of bearers of the UE group in the same APN; and

AMBR of non-GBR bearers of the UE group in the same APN.

Further, if the number of bearers or PDP contexts of the UE groupreaches or exceeds the maximum number of bearers or PDP contexts of theUE group, the controlling module 82 in this embodiment may reject ordiscard the session management request message of the UEs in the UEgroup, or discard the data of the UEs in the UE group, or delete thebearers or PDP contexts of the UEs in the UE group. For detaileddescription, see the related description in the third embodiment.

Further, if the access rate of the UE group reaches or exceeds themaximum access rate of the UE group, the controlling module 82 in thisembodiment may reject or discard the session management request messageof the UEs in the UE group, or discard the data of the UEs in the UEgroup. For detailed description, see the related description in thethird embodiment.

Further, if the total bandwidth of bearers of the UE group reaches orexceeds the AMBR of the bearers of the UE group, or if the totalbandwidth of non-GBR bearers of the UE group reaches or exceeds the AMBRof non-GBR bearers of the UE group, or if the total bandwidth of bearersof the UE group in the same APN reaches or exceeds the AMBR of bearersof the UE group in the same APN, or if the total bandwidth of non-GBRbearers of the UE group in the same APN reaches or exceeds the AMBR ofnon-GBR bearers of the UE group in the same APN, the controlling module82 in this embodiment may discard the data that exceeds the AMBR orcharge for the data that exceeds the AMBR.

Further, if the controlling module 82 in this embodiment rejects thesession management request message of the UEs in the UE group, thecontrolling module 82 may send a session management reject message tothe mobility management element, where the session management rejectmessage carries time indication information (called first timeindication information) and/or a cause value, where:

the first time indication information is used to instruct the mobilitymanagement element to reject or discard the access request message ofthe UEs in the UE group within the time range indicated by the firsttime indication information; or

the first time indication information is used to instruct the mobilitymanagement element to accept the access request message of the UEs inthe UE group beyond the time range indicated by the first timeindication information; or

the cause value is used to notify the mobility management element thatthe gateway device is in the congested/overloaded state.

FIG. 9 is a schematic structural diagram of still another gateway deviceaccording to a ninth embodiment of the present invention. As shown inFIG. 9, the gateway device in this embodiment may include a sendingmodule 91 adapted to send an indication message to a mobility managementelement, where the indication message indicates that the gateway deviceis congested/overloaded or that an application server isfailed/congested/overloaded/unreachable/misbehaving, so that themobility management element

selects other gateway devices for UEs that access the gateway device; or

rejects or discards access request messages of UEs served by the gatewaydevice or the application server; or

detaches UEs on the gateway device or the application server; or

deletes bearers of the UEs on the gateway device or the applicationserver.

Both the method in the fifth embodiment and the function of the gatewaydevice in the sixth embodiment may be implemented by the gateway deviceprovided in this embodiment.

With the gateway device provided in this embodiment, when the gatewaydevice is congested/overloaded or the application server isfailed/congested/overloaded/unreachable/misbehaving, the gateway devicemay send an indication message to a mobility management element, so thatthe mobility management element performs congestion/overload controlaccording to the indication message sent by the gateway device. In thisway, congestion/overload control can be performed on the gateway device,and congestion/overload caused by a large number of UEs on the gatewaydevice is avoided.

FIG. 10 is a schematic structural diagram of still another gatewaydevice according to a tenth embodiment of the present invention. Asshown in FIG. 10, compared with the ninth embodiment, the gateway devicein this embodiment may further include a first controlling module 1001and a second controlling module 1002. The first controlling module 1001may discard the data of UEs in the following group: the group thatcauses congestion/overload of the gateway device, the group served bythe failed/congested/overloaded/unreachable/misbehaving applicationserver or congested/overloaded gateway device, or the group that causesthe application server to befailed/congested/overloaded/unreachable/misbehaving; the secondcontrolling module 1002 may delete the bearers of UEs in the followinggroup: the group that causes congestion/overload of the gateway device,the group served by thefailed/congested/overloaded/unreachable/misbehaving application serveror congested/overloaded gateway device, or the group that causes theapplication server to befailed/congested/overloaded/unreachable/misbehaving.

With the gateway device provided in this embodiment, when the gatewaydevice is congested/overloaded or the application server isfailed/congested/overloaded/unreachable/misbehaving, the gateway devicemay send an indication message to a mobility management element, so thatthe mobility management element performs congestion/overload control; orthe gateway device may perform congestion/overload control by itself. Inthis way, congestion/overload control is further performed on thegateway device, and congestion/overload caused by a large number of UEson the gateway device is avoided.

FIG. 11 is a schematic structural diagram of a mobility managementelement according to an eleventh embodiment of the present invention; asshown in FIG. 11, the mobility management element includes a receivingmodule 1101 and a controlling module 1102. The receiving module 1101receives an indication message sent by a gateway device, where theindication message indicates that the gateway device iscongested/overloaded or that an application server isfailed/congested/overloaded/unreachable/misbehaving. The controllingmodule 1102 selects other gateway devices for UEs that access thegateway device; or rejects or discards access request messages of UEsserved by the gateway device or the application server; or detaches UEson the gateway device or the application server; or deletes bearers ofthe UEs on the gateway device or the application server.

Both the method in the fifth embodiment and the function of the mobilitymanagement element in the sixth embodiment may be implemented by themobility management element provided in this embodiment.

With the mobility management element provided in this embodiment, whenthe gateway device is congested/overloaded or the application server isfailed/congested/overloaded/unreachable/misbehaving, the mobilitymanagement element may perform congestion/overload control according tothe indication message sent by the gateway device, so thatcongestion/overload control can be performed on the gateway device, andcongestion/overload caused by a large number of UEs on the gatewaydevice is avoided.

Further, if the controlling module 1102 in this embodiment rejects theaccess request messages of UEs served by the gateway device or theapplication server, the controlling module 1102 may send an accessrequest reject message to the UEs, where the access request rejectmessage may carry time indication information (called second timeindication information), where:

the second time indication information is used to instruct the UEs inthe group not to send access request messages within the time rangeindicated by the second time indication information; or

the second time indication information is used to instruct the UEs inthe group to send access request messages beyond the time rangeindicated by the second time indication information.

It should be noted that the congestion/overload described in theembodiments of the present invention refers to congestion or overload.

It should be noted that the embodiments of the present invention may beapplied not only in the M2M communication system but also in othercommunication systems, for example, a Human to Human (H2H) communicationsystem, which is not limited by the embodiments of the presentinvention.

It is understandable to persons skilled in the art that all or part ofthe steps of the methods in the foregoing embodiments can be implementedby relevant hardware instructed by a program. The program may be storedin a computer readable storage medium. When the program runs, the stepsof the methods in the foregoing embodiments are executed, and thestorage medium may be any medium that can store program codes, such as aRead Only Memory (ROM), a Random Access Memory (RAM), a magnetic diskand a Compact Disk-Read Only Memory (CD-ROM).

Finally, it should be noted that the embodiments of the presentinvention are intended for describing the technical solutions of thepresent invention other than limiting the present invention. Althoughthe present invention is described in detail with reference to theforegoing embodiments, persons of ordinary skill in the art shouldunderstand that modification and substitutions can be made to thetechnical solutions of the present invention or some technical featuresthereof without departing from the spirit and scope of the presentinvention.

What is claimed is:
 1. A congestion/overload control method comprising:obtaining, by a gateway device, information about a congestion/overloadcontrol parameter or policy of a User Equipment (UE) group; andrejecting, by the gateway device, request messages of UEs in the UEgroup upon the congestion/overload control parameter or policy of the UEgroup being reached or exceeded, including sending a first timeindication information to a mobility management element, wherein (a) thefirst time indication information indicates a time range for themobility management element to (i) reject request messages of the UEs inthe UE group or (ii) select another gateway device for the UEs in the UEgroup, and (b) the information about the congestion/overload controlparameter or policy of the UE group comprises any one or combination ofthe following: a maximum number of bearers or Packet Data Protocol (PDP)contexts of the UE group, and a maximum access rate of the UE group,wherein the access rate is a rate of activating bearers or PDP contextsof the UE group.
 2. The method according to claim 1, wherein: if thenumber of the bearers or PDP contexts of the UE group reaches or exceedsthe maximum number of the bearers or PDP contexts of the UE group, therequest messages of the UEs in the UE group are rejected; or if theaccess rate of the UE group reaches or exceeds the maximum access rateof the UE group, the request messages of the UEs in the UE group arerejected.
 3. The method according to claim 1, wherein the first timeindication information is back-off time.
 4. The method according toclaim 1, wherein the method further comprises: after receiving the firsttime indication information, rejecting, by the mobility managementelement, request messages of the UEs in the UE group within a time rangeindicated by the first time indication information; or selecting, by themobility management element, other gateway device for the UEs in the UEgroup.
 5. The method according to claim 1, wherein request messages ofthe UEs is session management request message.
 6. The method accordingto claim 1 wherein the obtaining, by the gateway device, the informationabout the congestion/overload control parameter or policy of the UEgroup, comprises: obtaining, by the mobility management element, theinformation about the congestion/overload control parameter or policy ofthe UE group from configuration information, and notifying the gatewaydevice of the information about the congestion/overload controlparameter or policy of the UE group through a session managementmessage; or obtaining, by the mobility management element, theinformation about the congestion/overload control parameter or policy ofthe UE group from a subscription profile repository, and notifying thegateway device of the information about the congestion/overload controlparameter or policy of the UE group through a session managementmessage; or obtaining, by the mobility management element, theinformation about the congestion/overload control parameter or policy ofthe UE group from UE contexts, and notifying the gateway device of theinformation about the congestion/overload control parameter or policy ofthe UE group through a session management message; or obtaining, by thegateway device, the information about the congestion/overload controlparameter or policy of the UE group from configuration information ofthe gateway device; or obtaining, by the gateway device, the informationabout the congestion/overload control parameter or policy of the UEgroup from a database.
 7. The method according to claim 6, wherein theconfiguration information of the gateway device is information about thecongestion/overload control parameter or policy of the UE groupconfigured according to a group ID of the UE group, and the obtainingthe information about the congestion/overload control parameter orpolicy of the UE group from the configuration information of the gatewaydevice comprises: receiving, by the gateway device, a session managementrequest of the UE, wherein the request message carries the group ID ofthe UE group; and querying, by the gateway device according to the groupID of the UE group, the information about the congestion/overloadcontrol parameter or policy of the UE group configured on the gatewaydevice.
 8. The method according to claim 1, wherein the UE group isidentified by an Access Point Name (APN).
 9. A gateway devicecomprising: a processor, and a non-transitory computer-readable storagemedium storing a program to be executed by the processor, the programincluding instructions for: obtaining information about acongestion/overload control parameter or policy of a User Equipment (UE)group; and rejecting request messages of UEs in the UE group upon thecongestion/overload control parameter or policy of the UE group beingreached or exceeded, including sending a first time indicationinformation to a mobility management element, wherein (a) the first timeindication information indicates a time range for the mobilitymanagement element to (i) reject request messages of the UEs in the UEgroup or (ii) select another gateway device for the UEs in the UE group,and (b) the information about the congestion/overload control parameteror policy of the UE group comprises any one or combination of thefollowing: a maximum number of bearers or Packet data Protocol (PDF)contexts of the UE group, and a maximum access rate of the UE group,wherein the access rate is a rate of activating bearers or PDP contextsof the UE group.
 10. The gateway device according to claim 9, wherein inrejecting request messages of UEs in the UE group, the program includesinstructions for: rejecting the request messages of the UEs in the UEgroup upon number of the bearers or PDP contexts of the UE groupreaching or exceeding the maximum number of the bearers or PDP contextsof the UE group; or rejecting the request messages of the UEs in the UEgroup upon access rate of the UE group reaching or exceeding the maximumaccess rate of the UE group.
 11. The gateway device according to claim9, wherein request messages of the UEs is session management message.12. The gateway device according to claim 9, wherein in obtaining theinformation about the congestion/overload control parameter or policy ofthe UE group, the program includes instructions for: obtaining theinformation about the congestion/overload control parameter or policy ofthe UE group from configuration information, and notifying the gatewaydevice of the information about the congestion/overload controlparameter or policy of the UE group through a session managementmessage; or obtaining the information about the congestion/overloadcontrol parameter or policy of the UE group from a subscription profilerepository, and notifying the gateway device of the information aboutthe congestion/overload control parameter or policy of the UE groupthrough a session management message; or obtaining the information aboutthe congestion/overload control parameter or policy of the UE group fromUE contexts, and notifying the gateway device of the information aboutthe congestion/overload control parameter or policy of the UE groupthrough a session management message; or obtaining the information aboutthe congestion/overload control parameter or policy of the UE group fromconfiguration information of the gateway device; or obtaining theinformation about the congestion/overload control parameter or policy ofthe UE group from a database.
 13. The gateway device according to claim12, wherein the configuration information of the gateway device isinformation about the congestion/overload control parameter or policy ofthe UE group configured according to a group ID of the UE group, and inobtaining the information about the congestion/overload controlparameter or policy of the UE group from configuration information ofthe gateway device, the program includes instructions for: receiving arequest message of the UE, wherein the request message carries the groupID of the UE group; and querying according to the group ID of the UEgroup, the information about the congestion/overload control parameteror policy of the UE group configured on the gateway device.
 14. Thegateway device according to claim 9, wherein the UE group is identifiedby an Access Point Name (APN).
 15. A congestion overload control methodcomprising: receiving, by a mobility management element, rejection froma gateway device when a congestion/overload control parameter or policyof a User Equipment (UE) group is reached or exceeded, including sendinga first time indication information to a mobility management element,wherein (a) the first time indication information indicates a time rangefor the mobility management element to (i) reject, by the mobilitymanagement element, request messages of the UEs in the UE group or (ii)select, by the mobility management element, another gateway device forthe UEs in the UE group, and (b) the congestion overload controlparameter or policy of the UE group comprises any one or combination ofthe following: a maximum number of bearers or Packet Data Protocol (PDP)contexts of the UE group, and a maximum access rate of the UE group,wherein the access rate is a rate of activating bearers or PDP contextsof the UE group.
 16. The method according to claim 15, wherein the UEgroup is identified by an Access Point Name (APN).
 17. The methodaccording to claim 15, wherein the rejecting from the gateway devicecomprising a first time indication information, and rejecting requestingmessages of the UEs in the UE group, or selecting another gateway devicefor the UEs in the UE group comprises: rejecting requesting messages ofthe UEs in the UE group within a time range indicated by the first timeindication information, or selecting another gateway device for the UEsin the UE group within a time range indicated by the first timeindication information.
 18. A mobility management element comprising: aprocessor, and a non-transitory computer-readable storage medium storinga program to be executed by the processor, the program includinginstructions for: receiving a rejection from a gateway device when acongestion overload control parameter or policy of a User Equipment (UE)group is reached or exceeded, including sending a first time indicationinformation to a mobility management element, wherein (a) the first timeindication information indicates a time range for the mobilitymanagement element to (i) reject request messages of the UEs in the UEgroup, or (ii) select another gateway device for the UEs in the UEgroup, and (b) the congestion/overload control parameter or policy ofthe UE group comprises any one or combination of the following: amaximum number of bearers or Packet Data Protocol (PDP) contexts of theUE group, and a maximum access rate of the UE group, wherein the accessrate is a rate of activating bearers or PDP contexts of the UE group.19. The mobility management element according to claim 18, wherein theUE group is identified by an Access Point Name (APN).
 20. The mobilitymanagement element according to claim 18, wherein the rejecting from thegateway device comprising a first time indication information, rejectingrequesting messages of the UEs in the UE group, or selecting anothergateway device for the UEs in the UE group comprises: rejectingrequesting messages of the UEs in the UE group within a time rangeindicated by the first time indication information, or selecting anothergateway device for the UEs in the UE group within a time range indicatedby the first time indication information within a time range indicatedby the first time indication information.
 21. A system comprising: agateway device configured to obtain information about acongestion/overload control parameter or policy of a User Equipment (UE)group, and reject request messages of UEs in the UE group upon thecongestion/overload control parameter or policy of the UE group isreached or exceeded, including sending a first time indicationinformation to a mobility management element, wherein (a) the first timeindication information indicates a time range for the mobilitymanagement element to (i) reject request messages of the UEs in the UEgroup or (ii) select another gateway device for the UEs in the UE group,and (b) wherein the information about the congestion/overload controlparameter or policy of the UE group comprises any one or combination ofthe following: a maximum number of bearers or Packet Data Protocol (PDP)contexts of the UE group, and a maximum access rate of the UE group,wherein the access rate is a rate of activating bearers or PDP contextsof the UE group; and a mobility management element configured to receivethe rejection from the gateway device, and reject request messages ofthe UEs in the UE group within a time range indicated by the first timeindication information or select another gateway device for the UEs inthe UE group within a time range indicated b the first time indicationinformation.
 22. The system according to claim 21, wherein the UE groupis identified by an Access Point Name (APN).
 23. A non-transitorycomputer readable medium storing instructions that when executed by acomputer processor, cause the processor to perform the steps of: obtaininformation about a congestion/overload control parameter or policy of aUser Equipment (UE) group; and reject request messages of UEs in the UEgroup upon the congestion/overload control parameter or policy of the UEgroup being reached or exceeded, including sending a first timeindication information to a mobility management element, wherein (a) thefirst time indication information indicates a time range for themobility management element to (i) reject request messages of the UEs inthe UE group or (ii) select another gateway device for the UEs in the UEgroup, and (b) the information about the congestion/overload controlparameter or policy of the UE group comprises any one or combination ofthe following: a maximum number of bearers or Packet Data Protocol (PDP)contexts of the UE group, and a maximum access rate of the UE group,wherein the access rate is a rate of activating bearers or PDP contextsof the UE group.
 24. The non-transitory computer readable mediumaccording to claim 23, wherein the UE group is identified by an AccessPoint Name (APN).
 25. A non-transitory computer readable medium storinginstructions that when executed by a computer processor, cause theprocessor to perform the following: receiving a rejection from a gatewaydevice when a congestion/overload control parameter or policy of a UserEquipment (UE) group is reached or exceeded, including sending a firsttime indication information to a mobility management element, wherein(a) the first time indication information indicates a time range for themobility management element to (i) reject request messages of the UEs inthe UE group, or (ii) select another gateway device for the UEs in theUE group, (b) wherein the congestion/overload control parameter orpolicy of the UE group comprises any one or combination of thefollowing: a maximum number of bearers or Packet Data Protocol (PDP)contexts of the UE group, and a maximum access rate of the UE group,wherein the access rate is a rate of receiving attach requests, PDNconnectivity requests, or activating bearers or PDP contexts of the UEgroup.
 26. The non-transitory computer readable medium according toclaim 25, wherein the UE group is identified by an Access Point Name(APN).